text: 
  /**
   * Inserts a certain character until a has the desired length
   * e.g. padLeft('foo', 5, '_') -> '__foo'
   * e.g. padLeft(  '2', 2, '0')   -> '02'
   */
  function padLeft(val, num, str) {
    return '00000'.replace(/0/g, str).slice(0, num - val.length) + val;
  }
  
  // YOUR CODE GOES HERE
  module.exports = padLeft;